The new Second Avenue Subway will only have limited service when it gets rolling New Year’s Day, official said Monday.

Gov. Andrew Cuomo and the MTA will nominally keep their promise of launching the line by around its previously scheduled deadline, at noon Jan. 1.

Trains are expected to run every 6 minutes during peak hours — but only between 6 a.m. and 10 p.m. for the first week-and-a-half, officials said.

Overnight service isn’t slated to start until Jan. 9.